1. Field of the Invention
This invention generally relates to a vehicle, comprising a vehicle body, a chassis with wheels and tires on which the vehicle rests, a number of vehicle suspension springs and shock absorbers which are mounted between the wheels and the vehicle body and which execute a change, in their axial length as a function of the wheel spring travel, in the form of a displacement between a piston fastened to a piston rod and a pressure tube of the shock absorber, and thereby displace a damping medium through a damping device, as well as means to fasten the piston rod and the pressure tube to the vehicle body and the wheel.
2. Background Information
It is generally known from technical literature that the interface between the tires and the road has a major influence on the comfort experienced by a driver. On one hand, there tend to be rough spots in the road, which, in terms of the total suspension system, can be evaluated in terms of an oscillation which varies from more than 15 Hz to approximately 60 Hz in connection with very small amplitudes. In addition, even with a very small radial tire run-out, there are frequencies which are in the range of approximately 30 to 100 Hz, and which can be very unpleasant for the driver and passengers in the vehicle. There is also the characteristic frequency of the vehicle springs.
Of course, the acoustical problem of frequencies from 30 to 100 Hz could be solved by massive use of insulation material, but that would increase the weight of the vehicle. Nor would it be very efficient to reduce the damping of the shock absorbers, since that would have a negative impact on the handling and safety of the vehicle.